The Israel Air Force's readiness was tested Tuesday evening in an incident, the details of which are not being released in full. The Israel Air Force's Northern Control Unit spotted fighter jets from a foreign country approaching Israel's air space. Israeli fighter jets were scrambled to intercept the foreign jets, out of concern that they were involved in a hostile attempt of some sort. After a short time it became clear that the foreign jets were not attempting hostile action and the IAF jets returned to their bases. According to Channel 2 news, the incident occurred in the skies west of Haifa and the foreign jets had been participating in an exercise. Israel's nearest neighbors to the west and north include Cyprus and Turkey. One of the scenarios that the IDF is concerned about involves a Muslim terrorist who flies a jet into Israeli airspace in order to carry out an attack.